MFPKEY_WMAAECMA_FEATR_ECHO_LENGTH Property

Specifies the duration of echo that the acoustic echo cancellation (AEC) algorithm can handle, in milliseconds.

Constant for IPropertyBag

Available only by using IPropertyStore.

Data Type

VT_I4

Default Value

256

Applies To

• Voice Capture DSP

Remarks

The AEC algorithm uses an adaptive filter whose length is determined by the duration of the echo. It is recommended that applications use one of the following values:

• 128
• 256
• 512
• 1024

The default value is 256 milliseconds, which is sufficient for most office and home environments. Before setting this property, you must set the MFPKEY_WMAAECMA_FEATURE_MODE property to VARIANT_TRUE.

The DSP uses this property only when AEC processing is enabled.

Requirements

Minimum supported client	Windows Vista
Minimum supported server	Windows Server 2008
Header	Wmcodecdsp.h

See Also

Properties

Using the Voice Capture DSP

Voice Capture DSP

 

 

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Build date: 4/7/2010